diff --git a/internal/transport/grpc/grpc.go b/internal/transport/grpc/grpc.go
index d5c352e..d880a45 100644
--- a/internal/transport/grpc/grpc.go
+++ b/internal/transport/grpc/grpc.go
@@ -71,10 +71,10 @@ func (s *AuthDBServer) Registration(ctx context.Context, req *api.RegistrationRe
 	s.mu.Lock()
 	defer s.mu.Unlock()
 
-	// //
-	// if _, ok := s.users[req.GetLogin()]; ok {
-	// 	return nil, errors.New("login already registered")
-	// }
+	//
+	if _, ok := s.users[req.GetLogin()]; ok {
+		return nil, errors.New("login already registered")
+	}
 
 	//
 	s.id = s.id + 1